BAND-STOP FILTER Russian patent published in 2019 - IPC H01P1/20 H01P7/04 

FIELD: radio equipment.

SUBSTANCE: invention relates to radio engineering and specifically to UHF equipment and is intended for creation of band-stop filters of decimeter range of frequencies based on dielectric resonators. Band-stop filter comprises a shielded coaxial line bounded at the ends by transitions to be connected to the path, n disk dielectric resonators, each of which is installed axisymmetrically on cylindrical dielectric support in hollow metal cylindrical section. Cylindrical section is limited on one side by base plate, and on other side by metal cover with screw of frequency adjustment, made with possibility of axial movement. Coaxial line is equipped with conductors of loops connected to its internal conductor through distances in one quarter of wave length, and each of conductors of loops is prolonged inside cavity of cylindrical section in form of a loop of connection. Communication loop is made in form of arc facing side surface of disk dielectric resonator so that end of communication loop conductor is inserted into additional hole made in wall of cylindrical section, with the possibility of movement of the communication loop conductor with subsequent attachment of the end of the communication loop conductor in the wall of the cylindrical section, for example with soldering. Disc dielectric resonators are installed, for example, in order of links 1-2-3 of three-link band-stop filter and are tuned to the smallest, largest and average resonant frequencies respectively, and each disk dielectric resonator made of high-permeable dielectric material has U-shaped characteristic of temperature coefficient of frequency at relative care of resonant frequency of working type of vibrations of disk dielectric resonator with minimum value of temperature coefficient of frequency in area of normal temperature. Height of cylindrical support is selected within 0.85–1.35 of height of disk dielectric resonator at ratio of its own height to diameter within 0.4–0.5. Screw of frequency adjustment is made of metal with value of coefficient of temperature linear expansion, different from value of coefficient of temperature linear expansion of metal of cylindrical section and cover, on which it is installed.

EFFECT: invention improves stability of electrical characteristics of band-stop filters by increasing thermal stability and simplifying filter adjustment.

1 cl, 3 dwg